Sleepy alarm system activated by heart pulse meter

Abstract

This invention provides a sleepy alarm apparatus for a vehicle driver, which is activated by a heart pulse meter, of which the measured heart pulse rate is lower than the preset threshold sleepy pulse rate. When a driver is sleepy while driving, the pulse rate is gradually decreasing. This invention continuously monitors the time interval for the predetermined number of the driver's pulses and converts the time interval into a pulse rate. If the measured pulse rate is lower than the preset threshold pulse rate, the system will trigger an alarm unit, which is a part of the present invention. The preset threshold pulse rate can be adjusted by the increase or decrease switch. The apparatus may be made to be wearable on a wrist or made to be attachable on the steering wheel of the vehicle being driven. In which case, the device includes a cuff for placing a finger in it in order to monitor the heart pulses.

What is claimed is:  
     
       1. A sleepy alarm system activated by detecting a lower pulse rate than a preset threshold sleepy pulse rate for a vehicle driver, of which a value is initially set for an average human pulse rate expected while a person is sleepy, and fine adjusted for the preset threshold sleepy pulse rate of the driver, comprising: a heart pulse meter; an alarm unit; an INCREASE switch and a DECREASE switch to fine adjust the preset threshold sleepy pulse rate; and a wakeup switch to invoke either sleepy pulse rate adjustment function, or normal display function. 
     
     
       2. A sleepy alarm system according to  claim 1 , wherein the heart pulse meter further comprises: 
       a) a pulse sensor to input a pulse signal;  
       b) a waveshaping circuit to shape input signal to a square wave;  
       c) a microcontroller for continuously;  
       measuring a time interval of every predetermined number of pulses,  
       converting the measured time interval to a pulse rate,  
       setting an initial threshold sleepy pulse rate,  
       comparing the measured pulse rate with the preset threshold sleepy pulse rate,  
       generating a warning signal if any comparison result shows that the measured pulse rate is lower than the preset threshold sleepy pulse rate; and  
       d) a display unit to display: the measured pulse rate, flashing heart image, and the preset threshold sleepy pulse rate.  
     
     
       3. A sleepy alarm system according to  claim 1 , wherein the alarm unit generates a warning sound when activated. 
     
     
       4. A sleepy alarm system according to  claim 1 , wherein the increase switch and the decrease switch are used to adjust the threshold sleepy pulse rate. 
     
     
       5. A method of generating a warning sound when a measured pulse rate of a vehicle driver is lower than a preset threshold sleepy pulse rate, which is initially set for a value of an average human pulse rate expected while a person is sleepy, and fine adjusted for the sleepy pulse rate of a specific person or the driver by INCREASE or DECREASE switch. 
     
     
       6. A method of generating a warning sound according to  claim 5 , wherein the method further comprises the following steps: 
       a) adjusting a threshold sleepy pulse rate with the INCREASE and DECREASE switches;  
       b) continuously measuring the time intervals for every predetermined number of pulses, and converting the measured time interval to a newly measured pulse rate;  
       c) continuously comparing every newly measured pulse rate with the preset threshold sleepy pulse rate; and  
       d) generating a warning sound if any comparison result shows that the newly measured pulse rate is lower than the preset threshold sleepy pulse rate.  
     
     
       7. A sleepy alarm system according to  claim 1 , a real time clock function can be combined in the alarm system. 
     
     
       8. A sleepy alarm system according to  claim 1 , wherein the WAKEUP switch provides the preset threshold sleepy pulse rate adjustment function, time adjustment function, and normal display function.